The use of digital technology continues to make rapid advances in many fields, and such digital technology is increasingly being applied to areas that once were completely relegated to the analog domain. One such area is distribution of motion pictures, which are increasingly being digitized and sold on DVDs (Digital Versatile Disks). The low cost and high quality afforded by DVDs have led to a boom in the sale of DVD players and DVDs.
There is a great deal of concern among content producers, e.g., the movie studios, about the release of motion pictures in digital formats. Content producers are particularly concerned about the next generation of DVDs, which will carry high definition video images. For example, a consumer can buy a DVD and duplicate it illegally without any loss in video quality if he can access the digital video signals. In order to prevent easy access to the digital video signals, most DVD players on the market today provide video output in analog format only.
DVDs containing high definition video images of motion pictures may not be available for sale unless the data on the DVDs can be protected from copying, both while on the disk and during its routing to a display device. Therefore, before consumer type DVD players with digital video outputs are available for sale, content producers and DVD player manufacturers preferably should agree on a secure way of sending digital video data from the DVD players to video display monitors or televisions.
Such digital video data is typically in parallel format and is converted to serial format (for digital video output) by a digital transmitter before being sent out on a digital display link to a video monitor or a television. On the display side, a digital receiver converts the serial data back into parallel format. The digital signal on the display link cable, if not protected, e.g., via encryption, can be intercepted and copied by a person wanting to steal the digital video data.
There is a standard digital display link for connecting a digital video signal from a computer to a display monitor, which is known as Digital Visual Interface (DVI). There is also a proposed standard for the content protection of such display links, known as High-bandwidth Digital Content Protection (HDCP), which provides for the encryption of digital video data between a digital video source and a display monitor using cryptographic keys. Both the digital video source and the display monitor should preferably have access to the cryptographic keys to encrypt and decrypt, respectively, the digital video data.
Therefore, it is desirable to provide an improved system and method for loading of the cryptographic keys to a digital video data encryptor on the digital video source side and the decryptor on the display monitor side.